It is increasingly common to give coloring to documents for use in offices. Colored documents, for instance, have greater visual appeal than monochromatically prepared documents, and an important passage in the colored document can be identified at a glance. Consequently, a color writing instrument using a color such as red is employed to write part of a record to be written in black only. Copying machines capable of accomplishing this effect have been proposed.
Japanese Patent Unexamined Application Publication No. 95457/1985, for instance, discloses a method of forming images of a plurality of original documents using different developing devices. Japanese Patent Unexamined Application Publication No. 166969/1985, on the other hand, discloses a method of reproducing in color data in an area of an original which has been specified for color recording. Further, Japanese Patent Unexamined Application Publication No. 239764/1985 discloses a method of making it possible to copy a specified image area from an original and reproduce it onto a desired area of copying paper and simultaneously copy the image area in a desired color.
However, (i) recording a portion of the image data on a document in a color other than black by means of a color-ink writing instrument is completely reliant on manual work, which is extremely inefficient. Moreover, if that portion of the image is colored unevenly, the quality of the document will not be maintained.
(ii) When part of an area or part of a document is recorded in color using a copying machine, monochromatic and color image data are required to be precisely coordinated with each other.
If character data or the like in a particular area is to be colored differently from data in another area, the reader is required to read the different colored data in the two areas. The problem is that the reader tends to feel visually fatigued. In the case of the electronic copying machine as disclosed in Japanese Patent Unexamined Application Publication No. 166969/1985, an area to be recorded in a color other than black can be specified only after the area designated by an input pen has been recorded in one color. This process of specifying the area to be colored is very troublesome.
An object of the present invention is to provide a color marking apparatus capable of expressing image data itself in a particular area with the same color as that used in another area and marking the image data by making the color of the background of the image data in the specified area different from another area.
Another object of the present invention is to provide a color marking apparatus capable of efficiently performing marking under various conditions of color and density of the document.
Still another object of the present invention is to provide a color marking apparatus with which a marking color can be designated on an area basis.
Another object of the present invention is to provide a color marking apparatus in which input data can readily be modified in order to alter the size of an area or the color for marking or to perform modified operation in consideration of color balance.